(1) Field of the Invention
This invention relates to an input line interface device and packet communication device and, more particularly, to an input line interface device for exercising interface control over packets on the input line side and a packet communication device for exercising communication control over packets.
(2) Description of the Related Art
With the rapid spread of the Internet, there has been a sharp increase in demand for IP (Internet protocol) traffic in recent years. Therefore, it is hoped that a high-speed large-capacity routing unit will be realized.
With conventional packet routing techniques, first a received packet is temporarily stored in a buffer in an input line section. Then a table prepared in advance is searched for an output route with an identifier in the packet as a key. And then the packet read from the buffer on the basis of output route information obtained is switched in a packet switching section and is sent to the appropriate output route.
With the above conventional packet routing techniques, packets have been processed in parallel in a plurality of packet processing sections. However, packet length is variable, so processing time in packet processing sections will differ. Routing IP traffic therefore can reverse the order of packets.
With the progress of optical multiplexing technologies, such as WDM, line speed is improving year by year. In addition, advanced packet processing relating to Layer 3 is needed. Therefore, providing a routing unit suitable for a high line speed and the diversity of networks is essential for realizing multimedia communication networks.